There are lots of good suggestions in this thread. Thanks.

If you want to do the whole arrangement in BiaB....For adding song specific MIDI riffs, you can use the melody or soloist tracks. Those don't get overwritten by generated tracks. You can also record an audio track. If you want multiple audio tracks, you can do that too, by either overdubbing, or moving an audio track to an artist performance track (using the audio menu).

Have Fun!
Peter Gannon
PG Music Inc.